Here is a brief list of tire sizes that will be close to factory size for the GD Subaru Impreza WRX and Subaru Impreza WRX STi.
Here are the applicable sizes. Each of these will work on a stock body WRX with the correct wheel/offset/suspension/alignment setup. May need fender rolling or other fender mods to fit without rubbing. 05-07 GD STi Fender mod.
225/45/17
235/45/17
245/40/17
255/40/17
Continue reading Correct Tire Sizes GD Subaru Impreza WRX and Subaru Impreza WRX STi
Here are a few little graphs I put together for a few different people to compare the different measurements of a few select size tires.
First up is a comparo of a select few 255/35/18 and 265/35/18
all tires listed in this graph are a 35 profile and 18″ diameter
Measuring Width is the wheel width that was used when measuring Tread width and Section width. Both of tread width and section width change with wheel width. More on this in a future article.
The width of the wheel is one of the key factors in selecting a wheel.
Go wider than stock?
Stay the same width?
Go narrower than stock?
These are a few questions that must be asked and answered before selecting a wheel. Not all wheels are available in all sizes.
I received a Private Message last night on one of the many forums I frequent and it is a common one. I’ve cropped down the users original question and cleaned up the answer a little.
Quote:
| Originally Posted by p********g
whats up man, im due for new tires and im kind of torn whether or not to go big for the “hey look at all my rubber” look or just to stick with what works. im running advan rcII’s 18×8.5 +45mm currently with 235/40 18’s. i have been thinking recently of upgrading to some 265/35 18’s and rolling the front and rear fender, but would first like to hear the pros and cons of each tire if possible. i dont do any track driving or autocross, but do hit up some canyon days here and there, but would mainly like the bigger tire for simply “the look” get back to me whenever you can at your earliest convenience, and be as candid as possible, thanks in advance |
 Continue reading 235 vs. 255 or 265 on an 8.5 wheel for an Impreza.
Yes, Low offset wheels hurt your wheel bearings more than stock.
the center line of the wheel being further from hub creates more stress than the stock offset.
is there “proof” of this? is there some mile marker where your bearings will explode if you run a +30mm offset on a Subaru? No.
Are you causing more stress than factory? Yes.
Will you need to replace them earlier? Yes.
I’m more than willing to read a report from someone who has proof of their broken wheel bearing vs. non broken low offset wheel bearing.
You wont see me wasting time figuring out the actual point of where it happens. Low offset wheels increase wear. Either you accept that or you stay with a higher offset wheel. End of Story.
-T3h_Clap
Running an Aggressive fitment on an STi isn’t easy but at the same time it isn’t impossible. For autox, track, show, street it is possible to find a wheel and tire combo that will meet the needs you’re looking for.
To run a 9.5″ wheel on an Subaru Impreza WRX STi GDB/F you’ll need the following